SMO 2009 Senior Round 1 Question 7
SMO · SMO 2009 Senior Round 1
Find the value of $\displaystyle\frac3{1!+2!+3!}+\frac4{2!+3!+4!}+\cdots+\frac{22}{20!+21!+22!}$.
$1-\frac1{24!}$
$\frac12-\frac1{23!}$
$\frac12-\frac1{22!}$
$1-\frac1{22!}$
$\frac12-\frac1{24!}$